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Дата изменения: Thu Mar 16 18:26:18 2000
Дата индексирования: Tue Oct 2 03:07:36 2012
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Поисковые слова: spectrum

Spectrum

Many light-curve identifications were made retrospectively from photographic plates originally obtained to patrol the sky for asteroids, supernovae and other variable phenomena. As a consequence the light curves were often incomplete so that symbiotic, cataclysmic and semi-regular variables were sometimes identified as RCBs.

RCB stars have a spectrum which resembles that of an F or G supergiant. Balmer lines are weak or absent, there are many lines of neutral atomic carbon and strong bands of molecular carbon (C₂ and CN). In one of the earliest analyses of stellar surface composition, it was shown that RCrB itself was extremely hydrogen-deficient. A handful of hot RCB stars have B-type spectra. These characteristics have enabled the identification of 34 RCB stars in the Galaxy to be confirmed.